Method for detecting, controlling and automatically compensating pressure in a polishing process

Abstract

The invention relates to a method for detecting, controlling and automatically compensating pressure in a polishing process, including: detecting a pressure between a polishing wheel and a polished workpiece by a detection shaft or a moment generated on the detection shaft, and outputting the detected pressure or moment to a controller; comparing the detected pressure or moment with a preset pressure or moment and determining whether there is a difference between them; calculating a compensation feeding amount based on the difference and outputting an adjustment signal to an adjustment shaft based on the compensation feeding amount; and moving the adjustment shaft correspondingly based on the adjustment signal so as to drive the polishing wheel or the polished workpiece to move correspondingly to adjust a relative position between the polishing wheel and the polished workpiece so that the difference keeps consistent.

The invention claimed is: 
     
       1. A method for detecting, controlling and automatically compensating pressure in a polishing process, wherein it comprises the following steps:
 detecting a pressure between a polishing wheel and a polished workpiece by a detection shaft in a direction of force, and outputting the detected pressure to a controller; 
 comparing by the controller the pressure detected by the detection shaft with a preset pressure and determining whether there is a difference between them, and if there is not a difference, repeating the last step, or if there is a difference, carrying out a next step; 
 calculating by the controller a compensation feeding amount based on the difference and outputting an adjustment signal to an adjustment shaft based on the compensation feeding amount; 
 moving the adjustment shaft correspondingly based on the adjustment signal so as to drive the polishing wheel or the polished workpiece to move correspondingly to adjust a relative position between the polishing wheel and the polished workpiece so that the pressure between the polishing wheel and the polished workpiece generated on the detection shaft by the pressure between the polishing wheel and the polished workpiece tends to be and keeps consistent with the preset pressure; and 
 in the polishing process, continuously repeating the foregoing steps to keep the pressure between the polishing wheel and the polished workpiece constant all the time, 
 wherein an axis of rotation of the polishing wheel is horizontal and a center of the workpiece is on a same horizontal line with a center of the polishing wheel, the detection shaft is mounted along a direction that is parallel to the direction of the pressure applied by the polishing wheel on the workpiece, and a force sensor is mounted at an end of the detection shaft. 
 
     
     
       2. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 1 , wherein the difference comprises a positive difference and a negative difference. 
     
     
       3. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 2 , wherein the polishing wheel is fixed to the detection shaft, and the detection shaft is fixed to the adjustment shaft. 
     
     
       4. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 3 , wherein if the controller determines that there is a positive difference between them, the controller calculates a negative compensation feeding amount based on the positive difference, and outputs the adjustment signal to the adjustment shaft based on the calculated negative compensation feeding amount, and the adjustment shaft moves away from the polished workpiece based on the adjustment signal so as to drive the polishing wheel to move away from the polished workpiece to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       5. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 3 , wherein if the controller determines that there is a negative difference between them, the controller calculates a positive compensation feeding amount based on the negative difference, and outputs the adjustment signal to the adjustment shaft based on the calculated positive compensation feeding amount, and the adjustment shaft moves towards the polished workpiece based on the adjustment signal so as to drive the polishing wheel to move towards the polished workpiece to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       6. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 2 , wherein the polishing wheel is fixed to the detection shaft, and the polished workpiece is fixed to the adjustment shaft. 
     
     
       7. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 6 , wherein if the controller determines that there is a positive difference between them, the controller calculates a negative compensation feeding amount based on the positive difference, and outputs the adjustment signal to the adjustment shaft based on the calculated negative compensation feeding amount, and the adjustment shaft moves away from the polishing wheel based on the adjustment signal so as to drive the polished workpiece to move away from the polishing wheel to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       8. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 6 , wherein if the controller determines that there is a negative difference between them, the controller calculates a positive compensation feeding amount based on the negative difference, and outputs the adjustment signal to the adjustment shaft based on the calculated positive compensation feeding amount, and the adjustment shaft moves towards the polishing wheel based on the adjustment signal so as to drive the polished workpiece to move towards the polishing wheel to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       9. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 2 , wherein the polishing wheel is fixed to the adjustment shaft, the polished workpiece is fixed to the detection shaft. 
     
     
       10. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 9 , wherein if the controller determines that there is a positive difference between them, the controller calculates a negative compensation feeding amount based on the positive difference, and outputs the adjustment signal to the adjustment shaft based on the calculated negative compensation feeding amount, and the adjustment shaft moves away from the polished workpiece based on the adjustment signal so as to drive the polishing wheel to move away from the polished workpiece to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       11. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 9 , wherein if the controller determines that there is a negative difference between them, the controller calculates a positive compensation feeding amount based on the negative difference, and outputs the adjustment signal to the adjustment shaft based on the calculated positive compensation feeding amount, and the adjustment shaft moves towards the polished workpiece based on the adjustment signal so as to drive the polishing wheel to move towards the polished workpiece to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       12. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 2 , wherein the polished workpiece is fixed to the detection shaft, the detection shaft is fixed to the adjustment shaft. 
     
     
       13. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 12 , wherein if the controller determines that there is a positive difference between them, the controller calculates a negative compensation feeding amount based on the positive difference, and outputs the adjustment signal to the adjustment shaft based on the calculated negative compensation feeding amount, and the adjustment shaft moves away from the polishing wheel based on the adjustment signal so as to drive the polished workpiece to move away from the polishing wheel to adjust the relative position between the polishing wheel and the polished workpiece. 
     
     
       14. The method for detecting, controlling and automatically compensating pressure in a polishing process according to  claim 12 , wherein if the controller determines that there is a negative difference between them, the controller calculates a positive compensation feeding amount based on the negative difference, and outputs the adjustment signal to the adjustment shaft based on the calculated positive compensation feeding amount, and the adjustment shaft moves towards the polishing wheel based on the adjustment signal so as to drive the polished workpiece to move towards the polishing wheel to adjust the relative position between the polishing wheel and the polished workpiece.